Sewing machine thread ratio control



Oct. 18, 1955 COOK SEWING MACHINE THREAD RATIO CONTROL 5 Sheets-Sheet 1 Filed May 7, 1952 IN V EN TOR.

MARTIN L. COOK TORNEY SEWING MACHINE THREAD RATIO CONTROL Oct. 18, 1955 300 2,720,854

SEWING MACHINE THREAD RATIO CONTROL Filed May '7, 1952 5 Sheets-Sheet 3 INVEN TOR. MARTIN L. COOK ATTORNEY M. L. cooK 2,720,854

SEWING MACHINE THREAD RATIO CONTROL Oct. 18, 1955 Filed May 7, 1952 5 Sheets-Sheet 4 IN VEN TOR. MARTIN L COOK ATTORNEY 1955 M. COOK 2,720,854

SEWING MACHINE THREAD RATIO CONTROL Filed May 7, 1952 5 Sheets-Sheet 5 FIG. 6

IN V EN TOR. MARTIN L. COOK ATTORNEY United States Patent SEWING MACHINE THREAD RATIO CONTROL Martin L. Cook, Western Springs, 111., assignor to Union Special Machine Company, Chicago, 111., a corporation of Illinois Application May 7, 1952, Serial No. 286,510 14 Claims. (Cl. 112242) The present invention relates to sewing machines and more particularly to thread control mechanisms for use with sewing machines having thread carrying stitch forming instrumentalities.

In sewing machines having a plurality of stitch forming instrumentalities, it is desirable to provide means for insuring uniform delivery of the thread or threads at a predetermined rate or rates to the various stitch forming instrumentalities. Uniform thread delivery is necessary for the formation of uniform stitches. Various means for improving uniformity of thread delivery have been suggested heretofore but such means have only partially solved the problems involved. For example, in U. S. Patent 2,332,932, issued July 30, 1940, on an invention of Albert S. Riviera, there is disclosed a sewing machine having thread controlling means that is driven by pull on one or more of the threads incident to consumption of the thread during stitch formation. Rotation of the wheel serves to deliver the threads in fixed ratios.

Such prior thread control means, however, do not completely overcome the difliculties of uniform stitch formation. For instance, in the use of these prior thread controls, inertia effects tend to cause tight stitches or thread breakage when the machine is started or the speed thereof is increased. On the other hand, when the machine is slowed or stopped, overthrow tends to cause loose stitch formation and sometimes skipping.

The principal object of the present invention has been to provide an improved thread control mechanism, for use with sewing machines having a plurality of stitch forming instrumentalities for carrying one or more threads, which will insure the production of uniform stitches under all conditions of operation.

A further object of the invention has been to provide an improved thread control mechanism of the above type in which thread metering is independent of the thickness of the work being sewn.

Another object of the invention has been to provide an improved thread control mechanism of the above type in which thread delivery to the stitch forming devices is independent of variations in thread conditions between the thread supply source and the control mechanism.

A feature of the invention has been to provide an improved thread control mechanism which is driven from the operating mechanism of the machine and is adapted to deliver predetermined amounts of thread to the stitch forming devices on each cycle of operation of the machine. This eliminates the need of a clutch or like device to suppress backlash of the control means.

Other and further objects and features of the invention will appear from the following description.

In accordance with the invention, a sewing machine having stitch forming and work feeding instrumentalities and driving connections therefor is provided with control means for delivering one or more threads to the stitch forming instrumentalities, the control means being positively driven by the driving connections to insure the production of uniform stitches. The control means comprises a rotatable member or members afiording one or more generally circular thread carrying surfaces with each of which a respective one of the threads may have peripheral contact for positive control thereof en route to the respective stitch forming instrumentality and a driving mechanism intercoupling a driven part of the sewing machine, such as one of the driving connections mentioned, with the rotatable member or members to rotate the latter. The arrangement is such that the thread or threads will be delivered by the control means to the stitch forming instrumentalities at the desired rate or rates. In the case of a plurality of threads, the relative peripheral velocities of the thread engaging surfaces of the rotatable member or members are proportional to the desired ratios.

The invention will now be described in greater detail with reference to the appended drawings wherein like reference characters have been used to denote like elements and in which:

Fig. l is a top plan view of a cup feed sewing machine having a thread control mechanism according to the invention and having the machine cover plate removed to afiord a view of the driving mechanism;

Fig. 2 is a side elevational view, partly in section, of the sewing machine of Fig. 1;

Fig. 3 is a front elevational view, partly in section, of the sewing machine of Fig. 1;

Fig. 4 is an exploded view of the thread ratio control devices shown in Figs. 1, 2 and 3;

Fig. 5 is a fragmentary sectional view illustrating a modification of the thread ratio control devices shown in Fig. 3 and the associated portion of the sewing machine frame; and

Fig. 6 is a side elevational view of the apparatus shown in Fig. 5.

Referring now to the drawings and more particularly to Figs. 1, 2 and 3, the thread ratio control mechanism has been illustrated in connection with a three thread cup feed sewing machine of known type, substantially as disclosed in U. S. Patents Nos. 2,043,748 and 2,043,749, issued June 9, 1936, to H. Hacklander. The invention is not, of course, limited to cup feed sewing machines or three thread sewing machines, but is adaptable to many types of sewing machines employing a plurality of stitch forming instrumentalities carrying one or more threads.

The sewing machine illustrated is provided with a frame 10 having a main shaft 11 journaled in projections 12 and 13 provided in either side of the frame 10. Shaft 11, which actuates all of the stitch forming instrumentalities and the work feeding and thread supplying mechanisms of the machine, extends beyond the projections 12 and 13 and carries at its ends combined hand and belt wheels 14 and 15.

Feeding of the work is accomplished by tangentiallyopposed, intermittently rotated vertical axis feeding wheels or cups 16 and 17 which intermittently advance,

between them, a plurality of superposed fabric edges for presentation to the stitch forming instrumentalities of the machine. These instrumentalities include a needle 18 and a pair of loopers 19 and 20 for manipulating their respective threads in known manner to produce an overedge seam along the fabric edges as they are advanced by the feed cups. The needle 18 is secured to an endwise reciprocating needle bar 21. The looper 19 is secured to an oscillating shaft 22 which is inclined at a small angle to the horizontal, while the overedge looper 20 is secured to a similarly inclined shaft 23 which is reciprocated endwise as well as oscillated about its axis.

' in properly timed relation through actuating mecha- The shafts 21, 22 and 23 derive their movements side of frame by means" ofscieWs? ried by the wall of the frame; The

ni'sm's' driven by eccentrics or cranks on the main'shaft 11,..1in known manner. a

A rock member (Fig. 3) carried on a horizontal shaft 31 is provided with a lower arm 32 pivotally connected to a pitman by meansof a strap 33 on the latter and a pin 34 carried by the arm, The pitman is pro vided' with another strap 35Qconnected to an eccen rie secured to; the shaft 11L Rockmember 30' is also p'ro= vided with a: slo'tted upper'a'rni 36' which c'arris' a pin 37 by means ofwhich the arm is pivotally cofin'ected w one end of'a connecting rod 38.-

omen end' of con' 'necting rod 38 (Fi-g's.1 and-2)-'isconnected tetheop crating: arm 39a of: a one-way clutch 39 through $15311 and strap"connectionj40i- Clutch: 39, -which niav-ee;

the type disclosedin US. Patent: Noi- 2,398,652Qissued to' H; I, Le vesconre on Agni-1'16; 1946, sefves f6 trans:- mir intermittent motion from rock member 3016a rear feed cup shaft 412 siiaft tl which is jon rnaie'd; depending porti'o'n 42 (Fig; 2) of frarn'e 10;- QEi-XITES at its lower end the rear or inner feed cup 16.-

exfenr ofmovement of the feedeuponeach revolution of shaft 7 11 may' be: varied to: provide the desired stitch length by adjustingthe; pin 37' along the slot (nee how/re the arm36. H

Mounted atthe. top' of the rear feed cup shaft is shaft 45. This shaft is' formed in two parts; feed cup 17 is mounte'd'on-the lower end of the lower part of shaft so that feed cups 16 and 17 are diiven synchronously. in opposite directions by meshing gears 43 and 44. The lower portio'n of f r'ont feetl cup" slri'aftv 45 is journal'ed in a sleeve 46= carried by' a bracket 47.

ortion 48 01 the: Z

17 yieldingly. into engagement with the: cup 1 6 and to swing the cup 17 outwardly to' aklimited extent; away from cup 16 to enable theintroduction' of work Between the cups. p i

A vertical} shaft 55 'is carried by a bracket 56:rnolint ed on frame 10 by:screws"57 and SSW-Fig; 1 gear-Z smaller than: gears" 43 and is mounted on the upperflend 'of shaft anfifaifran'ged 59, which is? preferably to mesh withthe' gear 43. A b'evel gear60fis secured 'zonta'l shafti'62'; The 'dther en'd of shaft 62'eXtends oufside' the machine: frame" 10: Shaft" 62- is sllpi or'ted I part by'w bracket 63*(Figsi 1 and 3) aflixed -t thein 6 t 'and isfurther to be' hereinafter d'estzribedi carpp d by abushihg,

threadratiocontrolnunit 65.-

As shown in Figs. 1- through-4; the threadratio-control unit 65 comprises a single multi-grooved-wheel-66 whichis caIriedmn-thatportionof shaft 62 externaljto the machine frame 10-. Wheel 66iis provide d withthree grooves 67, 68 and 69. Grooves 67 and 68 which receive'therespective looper threads, are, in the illustrated embodiment, of 'equahdiameters. Groove 69, whi' :h"receives' the n'eedle tlirea'd, is of a slightlysm'allerdiameter because, in a sewing machine of' the type illustrated adapted particularly for the sea ingJof hosiery, a smaller.

amount of needlbth'read'than ileoper sharper: stitch is; I required; It is evidentthat'wh'eel"6'6 maybeprov-idid" with a number of'lgrooves equalte the'nu'rnb e'r ofl'threads to benietered" and that the relative" groove" diameters shaft- 62 drives a,

' 'a gear 43 which isarranged to mesh a gear 44: a secured to theupper end of a front or outer freedom? Tiid flbn fi desired ratios.

At the outer end of shaft 62 there is provided a releasable means, generally designated 70, for maintaining the wheel 66 in frictional driving contact with a clutch or driving disc 71. The releasable means '70 comprises a screw 72 and a nut 73 against which one end of a compression spring 74 (Fig. 4) bears. At its otherend the spring 74 bears against the bottom of a recessedportion 75 of a knurled collar 76.- The collar 76 is slidably mounted on shaft 62 and 'isarranged to be pressed against the wheel 66 by spring 74 to force wheel 66 into frictional driving engagement with the clutch disc 71. Clutch disc 71 is fixedltoshaft fl by set screws 77 The knurled collar 76 is provided with a notch 80 which is adapted to receive a pin 81 extending radially, from shaft 62, the depth of the notch being sufiicient to permit free axial movement of the'collar to the extent required-to urge" the winter-'66: into engagement with the disc: 71" when the notch is aligned with in it'is'desired torelease the spring ressurernsm wtieei 66; thereby to disengage wheel 66 from clutchdis'e'TI; the collar 76' may be pulled toward the outer en'd of shaft 62 until the notch- 80- cle'ars-the pin The' collar 76 is then: rotated in either direction so that its inner end bear's againstpin Sl rather than the wheel 66? Inord'ef po'sitivelytodisengage clutch disc, 71 and wheel -dti, so that wheel 66 mayfreely r'ot'ateon shaft 62 a lightsprin'g SZ and wheel66; Slight recesses may be provided in' orie or both: of thedisc 71 and wheel' 66 to accommodate spring: 82;- Uncoup'lingiofthewheel 66'fror'n the'disc 71-,-

inthe manner explained, facilitates the threading of the needle and loopers'. V

A; flanged-bushing 85, threaded at each-end, fit's into ahole 86 (Fig; 4) in the side ofthe overhangingportion48" 89 anda nut 90 are: provided 'over the threaded end" of bushing? 85' on the inside of the mari'xineframe; The washer 89' provides an oil seal and'the lock' nut9e s'ecur'el'y' s fastens bushing 85' to' the" machine frame". I,

V be provided-between the'eyelets mentioned'and the eyes The thread guidefand'tension disc bracket 87 is ro:- vided with a generally central flat portion 91' (Fig 4')? having a hole" 92. adapted to fit over the outer en'd of bushing 85"and' around the flange 88. A look washer 93 and anut 94 rigidly secure the bracket 87 to"the"fra'mef A small recess or well 95," (Fig 3) is -provide'd in over hangingiportiorr 48 to receive a-pin 96 projecting inwardly' from bracket 87 to alignuand prevent rotation of bracket 87; Bracket-87 is-provided'with two sets of thread guidingey'eletsr Oneset'cornprises'eyelets97, 98 and-'99e'iach arranged to'direct a respective thread from its associated---' groove in wheel 66 to its associated stitch formi'ngfel'e' merit. It willbeunderstood that other thread 'guides may of the needle'andloopers; Eyelets' 100, 101 -an'd 1 02,

comprisirigthe" other set carriedb'y bracket 87, arearranged to direct-the respective'threads from asso'cia'ted'i tension disc's 103, 104 and- 105to' the respectivegrooves ofwheel-66: Tension discs' 103;104andl05 are mount ed'on a sleeve l06 securedito bracket 87 bymeansof? nuts; 107 and 108 disposed on opposite' sides" of a hole" 109 *in bracket 87.

Thread tension between the threadsuppIY and the cob-' trol wheel may be adjusted suitably b'y varying-the pres sur'e' provided by 'a spring 110 acting between a spacer 103' and a kniirled' 'nut lfl' threaded on theend of'sl'eeve 106. Spacers 1'04" and105' are'p'rovided betweendiscs 103; and 104*and 104 and 105', respectively."

Each thread niay bewou'nd aroundwheel 66 in its r spective gfo'ov one of'n'iore times" aside'siredl If'is' dosh-"able" re wrap the" threads around thewheel a Suf ficient number of turns to prevent slippage in relation to the wheel. The number of turns required for this purpose will depend upon the tension applied to each thread as the threads are pulled up in the stitches. The thread tension discs may, if desired, be replaced with guide eyelets since the tension discs have no effect on thread tenion at the stitch forming instrumentalities.

Since the shaft 62 is driven through gears 43, 59, 60 and 61 from the rear feed cup shaft 45, any changes in speed of the machine or in stitch length will be reflected in the speed of rotation of shaft 62. Furthermore, since the control wheel 66 rotates with the shaft 62, such changes will directly affect the amounts of the respective threads metered by the wheel 66. It is evident, therefore, that metering of the proper amounts of the respective threads will be automatically adjusted to compensate for any changes in speed or stitch length. Metering of the threads in the proper relative ratios is, of course, ensured by causing the threads to pass around the associated grooves of the control wheel 66, the rate of delivery of each thread being determined by the peripheral speed of the surface of the engaged groove.

A unitary control wheel 66, as described above, may be replaced with a plurality of separate wheels 66A, 66B and 66C, as illustrated in Fig. 5. The unitary construction is simpler, easier to assemble and costs less. The separate construction, on the other hand, has the advantages of being easier to thread and of providing variable thread ratios through replacing one of the metering elements rather than the entire wheel.

Referring now to Figs. 5 and 6, the shaft 62 has mounted thereon three control wheels 66A, 66B and 66C, provided with grooves 67 68' and 69, respectively, for receiving the looper and needle threads. The wheel diameters in the groove portions thereof may be selected to provide the desired thread ratios. The wheels 66A, 66B and 66C are maintained in frictional driving relationship with each other and with the driving clutch disc 71' by use of a spring and collar arrangement identical to the one described hereinbefore in connection with the unitary control wheel 66 and forming a releasable means designated generally as 70'. Releasable means 70 comprises a screw 72', a nut 73, a spring 74 and a collar 76 having a recessed portion 75'. The mounting provided for shaft 62 is somewhat simpler than the one previously described and comprises a bushing 85' pressed into a hole 86' in the machine frame. A bracket 87' carrying the thread tension discs and the thread guiding eyelets is mounted directly on the machine frame by means of screws 120. The tension discs and thread guiding eyelets of Figs. 5 and 6 correspond to the like elements of Figs. 1-4.

When the releasable means 70' is pulled out, the control wheels 66A, 66B and 66C are freely rotatable individually on shaft 62, which facilitates threading thereof. Member 76 may be held in released position by disengaging its notch 80 from the pin 81 and turning it slightly to cause its inner surface to engage the pin.

The size of the control wheels in either the unitary or separate construction is inversely proportional to the gear ratio between the primary driving gear and the ultimately driven gear, i. e., between gears 43 and 61. With the usual standard stitch length of 17 or 18 stitches per inch, approximately six inches of needle thread and seven inches of each looper thread go into each two inch length of seam. It is evident, therefore, that if the thread groove diameters are smaller than the diameter of the feed cup, which will almost invariably be the case, a gear ratio of more than 3:1 will be required. For example, a gear ratio of 5:1 with a needle thread groove diameter of 1.17 and looper thread groove diameters of 1.36 will provide normal proportionate delivery of thread when feed cups of the conventional diameter, i. e., 1.95" are used.

While the invention has been described in relation to 6 specific embodiments thereof and for a specific use, it should be understood that it is not limited thereto for obvious modifications thereof will occur to those skilled in the art without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

l. A sewing machine, comprising a rotary shaft, 21 plurality of stitch forming and work feeding instrumentalities, driving connections therefor from said shaft for operating said stitch forming and work feeding instrumentaiities, said connections including an intermittently operable part and a control mechanism for delivering thread to said stitch forming instrumentalities for producing uniform stitches, said mechanism comprising ro tatable means affording at least one generally circular thread carrying surface with which said thread may have peripheral contact for positive control thereof en route to the stitch forming instrumentalities, and means intercoupling said intermittently operable part of'said driving connections and said rotatable means to rotate the latter, said means being arranged to impart a desired peripheral velocity to said thread carrying surface.

2. A sewing machine, comprising a rotary shaft, a plurality of stitch forming and work feeding instrumentalities, driving connections from said shaft for operating said work feeding instrumentalities, said driving connections being adjustable to vary the extent of feed movement of said work feeding instrumentalities upon each revolution of said shaft, and a control mechanism for delivering a plurality of threads to said stitch forming instrumentalities in desired ratios and at desired rates for producing uniform stitches, said mechanism comprising rotatable means affording a plurality of generally circular thread carrying surfaces With each of which a respective one of said threads may have peripheral contact for positive control thereof en route to the respective stitch forming instrumentalities, and means intercoupling said driving connections and said rotatable means to rotate the latter to an extent related to said feed movement of the work feeding instrumentalities, said means being arranged to impart peripheral velocities to said thread carrying surfaces corresponding to the desired rates of delivery of the threads carried thereby.

3. A sewing machine, comprising a rotary shaft, a plurality of stitch forming and work feeding instrumentalities, driving connections from said shaft for operating said work feeding instrumentalities, said driving connections being adjustable to vary the extent of feed movement of said work feeding instrumentalities upon each revolution of said shaft, and a control mechanism for delivering a plurality of threads to said stitch forming instrumentalities in desired ratios and at desired rates for producing uniform stitches, said mechanism comprising a rotatable member having a plurality of generally circular thread carrying surfaces with each of which a respective one of said threads may have peripheral contact for positive control thereof en route to the respective stitch forming instrumentalities, the relative diameters of said surfaces being proportional to said desired ratios, and driving means intercoupling said driving connections and said rotatable member to rotate the latter at a rate related to said feed movement of the work feeding instrumentalities and at which said threads will be delivered from said surfaces to said stitch forming instrumentalities at said desired rates.

4. A sewing machine, comprising a plurality of stitch forming and Work feeding instrumentalities, a rotary drive shaft, driving connections from said shaft for operating said work feeding instrumentalities, and a control mechanism for delivering a plurality of threads to said stitch forming instrumentalities in desired ratios and at desired rates for producing uniform stitches, said mechanism comprising a rotatable member having a plurality of generally circular thread carrying surfaces with each of which a respective one of said threads may have peripheral coni tact for positive control thereof err-route to the respective stit h forming instrumentalities, the relative diameters of i 'said urraciessein proportional as said desired ratios, and

drivingmeans intercoupling said feeding instrumentalities and said rotatable member to rotate the latter at a variable angular speed in relation to the angular speed of saidshaftto cause said threads to be delivered from said spifacesit a said stitch forming instrumentalities at said desired ratesa;

forming and work feeding instrumentalities and driving connections therefor, said driving connections for said work feeding instrumentalities being adjustable to vary the'extent of feed m'ovemen't imparted during each cycle of the machine, anda control mechanism for delivering a, plurality of threads to said stitch forminginstrumen talities in ds' at ratios'and at desired rates for producing stitches, said mechanism comprising a of rotatable generally annular thread carrying members with each of which a respective one of" said threads may contact for positive control thereof efn route" to the. respective stitch forming instrumentalities,

the.- relative outer diameters of said members pro"- por'tionall sa'id desired ratios, and means. intercoupling said feeding instrumentalities and said thread carrying to rotate the latter at a rate related to said feed movements and at which said threads will be deliveredfrom said members to said stitch forming instrumentalities at saiddesiredrate s. 1 V V I V 6 Av sewing machine, comprising a rotary shaft, a pluralitytof stitch formingand work feeding instrumentalities, driving connections from said shaft for operating saidwor l feeding instrumentalities, said connections being adjustable to mg the extent of operation of saidi work feeding instrumenta ties upon eachrevolution of said control mechanism for delivering a plurality of threads to said stitch. forming instrumentalities in dej sired ratios and at desired rates for producing uniform stitches, said mechanism comprising a plurality of rotat tmernbers tosaid stitch. forming instrumentalities at said desired rates. V t

7. A sewingmachine, comprising a rotary shaft, a-plu-- ralit y of stitch forming and. work feeding instrumentalities driv'ing connections from said shaft for operating 7 i said work feeding instrumentalities, said connections'being' adjustable to vary the, extent of operation of said work feedingi instrumentalities upon each revolution of said shaft, and a control mechanism for delivering a plurality of. threadsrto said stitch. forming instrumentalities in. de-' sired ratios, and at desired rates for producing uniform stitches, said mechanisms comprising a shaft connected to said 'driving connections for rotation thereof to extents: proportional, to: the extents of feed of said ,work feeding,

instrumentalities', and thread carrying means mounted on said shaft for rotation therewith, said thread carrying r- A sewing machine, comprising a plurality of stitch V element mounted on said shaft'for rotation therewith, and

meansl atfording a plurality of generally circular thread carrying'vsurfaces with each of which a respective one of saidthreads-mayhave peripheraltcontact for positive con-;

trol thereofen route to the respective stitch. forming in strurnentalities, the. relat ve-diameters ofsaid surfaces:

beingproportional to said desiredratiosQ t 8. A sewing machine comprising: awrotary shajffl a plu rality of stit cli forming and work", feeding instrumental? 'itiesg, connections from said operating; sard warr edmg instrumentalitiesasaid"connectionsrbeing adjustable to vary the extent of operation of said workfeedmg in's'trinnentalitics upon each'revolution' of said shaft, and a control mechanism for delivering a plurality of threads to said stitch forming instrumcntalities' in desired ratios and at desired rates for producing uniform stitches, said -rnechanisni comprising a shaft connected to said driving connections for rotation thereof to extents proportional to thelextent's of feed of said work feeding;

instrumentalities, a thread carrying member mounted on said shaft and being rotatable thereon, said thread carrying member affording a' plurality of generally circular thread carrying surfaces wi one of said threads may have peripheral contact for positive control thereof en route to the'respective stitch forming instrumentalities, the relative diameters of said surfaces being proportional to said desired ratios, a clutch releasable means for urging saidmember into frictional driving engagement with saidv clutch element.

9 A sewing machine, comprising a rotary shaft, a plu rality of stitch forming and workfeeding instrumentalities, driving connections from; s aid shaft for operating a said work feeding,instrumentalities said connections being adjustable to vary theextent of operation of said work feeding instrumentalitiesupon each' revolution of said 7 shaft, anda control mechanism for delivering a plurality ofthreads to said stitch forming instrumentalities in de-' sired ratios and at des red rates for producing uniform stitches, said me said driving connections for rotation thereof to extents proportional to the extents of feed of said 'work feeding instrumentalities, a plurality of: generally annular thread carrying members mounted on said; shaft and being rotatable thereon, each fgsaidthread carrying members afford ing agenerally circular thrcadi carrying surface with which arespectivefoneof saidthreadsfmay have peripheral contact for positive control thereof on route to the respectivestitch; forming instrumentality, the relative diametersof: said surfaces being proportional to said desired 7 ratios, a;clutch-e lement= mounted on' saidlshaft for rota-t tio'n' therewith, andreleasable' means for urging said mem bersinto frictional driving engagement with each other and with'saickdutch element.

1-0. A cupfeed sewing machine, comprising a frame having-gr hollow, lubricant retaining; portion, a' plurality of stitch; forming instrumentalit'ies, a pair, of, work adyancingrfeed; cups, a pair of feed'cup shafts for ro tating said feed cups, driving means for intermittently oppositely rotating. said feed cup shafts, and a control mechanismf;or delivering a plurality of threads to said Stitch fprrning instrumentalitiesin desired ratiosand at desired rates for producing uniform stitches, said mech anism cgmprzisinga thread control shaft, means includrmountedonone of said feed cup shafts s: at first n .and a. second gear mounted; on' said thread control shaft Within said; hollow lubricant retaining :portion of the frame; for' rotatingg said; thread. control shaft at atspeed proportional to, the operating speed: of said feed cups,

and thread carrying. means: mounted on said shaft'for" rotation' therewith, said thread carrying: means affording a} plurality of generally circular thread carrying sur-, faces with each f-whiclrarespective one ofsaidthreadsmay have peripheral contact for" positive control there 7 of enroute to: the respective stitchforming instrumen- I talities, the relative diameters of said surfaces being proportional to saiddesired ratios.

ll. A cup; feed sewing-machine, comprising aframe having a hollow lubricant retaining portion, a" plurality ofstitch forming instrumentalities, ,a pair of work advancing feedcups, a pair of feed cup shafts for r'otatingsaid 'feed cups, drivingtmeans for intermittently oppositely rotatinglsaid feed cup shafts, and a control;

mechanism for delivering a plurality of threads to said stitch forming instrumentalities int desired ratios andg-at form stitches, said mechdesired rates for producing uni th each of which a respective chanisrn comprising: a shaft connected to anism comprising a thread control shaft, means including a first gear mounted on one of said feed cup shafts and a second gear mounted on said thread control shaft Within said hollow lubricant retaining portion of the frame for rotating said thread control shaft at a speed proportional to the operating speed of said feed cups, thread carrying means mounted on said thread control shaft for rotation therewith, said thread carrying means affording a plurality of generally circular thread carrying surfaces with each of which a respective one of said threads may have peripheral contact for positive control thereof en route to the respective stitch forming instrumentalities, the relative diameters of said surfaces being proportional to said desired ratios, a clutch element mounted on said thread control shaft for rotation therewith, said clutch being exterior of said hollow lubricant retaining portion of said frame, and releasable means for urging said thread carrying means and said clutch element into frictional driving engagement with each other.

12. A cup feed sewing machine, comprising a plurality of stitch forming instrumentalities, a pair of work advancing feed cups, a pair of feed cup shafts for rotating said feed cups, driving means for intermittently oppositely rotating said feed cup shafts, and a control mechanism for delivering a plurality of threads to said stitch forming instrumentalities in desired ratios and at desired rates for producing uniform stitches, said mechanism comprising a thread control shaft, means including a driving gear mounted on one of said feed cup shafts and a driven gear mounted on said thread control shaft for rotating said thread control shaft at a speed proportional to the operating speed of said feed cups, thread carrying means mounted on said thread control shaft for rotation therewith, said thread carrying means alfording a plurality of generally circular thread carrying surfaces with each of which a respective one of said threads may have peripheral contact for positive control thereof en route to the respective stitch forming instrumentalities, the relative diameters of said surfaces being proportional to said desired ratios, a clutch disc rigidly mounted on said thread control shaft for rotation therewith, releasable means for urging said thread carrying means and said clutch disc into frictional driving engagement with each other, and a spring mounted on said thread control shaft between said thread carrying means and said clutch disc for positively disengaging the same upon release of said releasable means.

13. A sewing machine, comprising a rotary shaft, a plurality of stitch forming and Work feeding instrumentalities, driving connections from said shaft to said instrumentalities for operating the latter, said connec tions to said work feeding instrumentalities being adjustable to vary the extent of feed movement thereof upon each revolution of said shaft to thereby vary the length of the stitches formed, a thread control mechanism for delivering thread to said stitch forming instrumentalities, and driving means intercoupling said driving connections to said work feeding instrumentalities with said thread control mechanism for positively driving the latter at a rate related to said extent of feed movement, whereby the amount of thread delivered to said stitch forming instrumentalities varies with the length of the stitches formed.

14. A sewing machine comprising a rotary shaft, a plurality of stitch forming and work feeding instrumentalities, driving connections from said shaft to said instrumentalities for operating the latter, said driving connections to said work feeding mechanism being adjustable to vary the extent of feed movement imparted upon a revolution of said shaft, a thread control mechanism for delivering thread to said stitch forming instrumentalities, connections including a friction clutch for intercoupling a variably driven portion of said driving connections to said work feeding instrumentalities with said thread control mechanism, releasable pressure means for engaging said friction clutch, whereby said thread control mechanism may be connected with or disconnected from said driving connections to said work feeding instrumentalities, and means for positively disengaging said clutch in response to release of said releasable pressure means.

References Cited in the file of this patent UNITED STATES PATENTS 578,097 Frame Mar. 2, 1897 704,690 Saillet July 15, 1902 2,332,921 Kucera Oct. 26, 1943 

